Commitments and Contingencies - Narrative (Details) $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Jul. 31, 2023 item	Nov. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Loss Contingencies [Line Items]
Environmental loss contingency accrual			$ 20.0		$ 20.0			$ 22.0
Environmental Loss Contingency, Statement of Financial Position [Extensible Enumeration]			Accrued Liabilities		Accrued Liabilities			Accrued Liabilities
Minimum Carbon Dioxide Supply							$ 15.0
Maximum fee payable							$ 45.0
Number of petitions denied | item	26
Starfire Holding Corporation
Loss Contingencies [Line Items]
Ownership percentage by principal owner			99.60%		99.60%
Pension funding indemnity agreement with subsidiary			$ 250.0		$ 250.0
ACF
Loss Contingencies [Line Items]
Funded status of related party pension plan			$ 42.0		$ 42.0
Icahn Enterprises Holdings | ACF | Minimum
Loss Contingencies [Line Items]
Ownership percentage by principal owner			80.00%		80.00%
Mr. Icahn and affiliates | Minimum
Loss Contingencies [Line Items]
Affiliate ownership interest					80.00%
Mr. Icahn and affiliates | Icahn Enterprises G.P.
Loss Contingencies [Line Items]
Affiliate ownership in parent company general partner					100.00%
Mr. Icahn and affiliates | Icahn Enterprises Holdings
Loss Contingencies [Line Items]
Affiliate ownership interest					85.00%
Energy Segment
Loss Contingencies [Line Items]
Amount of quantifying alleged damages					$ 6.8
Expense (benefit)			$ 48.0	$ 135.0	37.0	$ 241.0
RFS position			$ 599.0		$ 599.0			$ 692.0
Insurance policies coverage limits		$ 50.0